Why Am I So Tired? 10 Common Causes of Fatigue

Prop your head up, pry your eyes open, and read on...

Why Am I So Tired? 10 Common Causes of Fatigue

I’m so tired. How often do you say this? How often do you hear other people say it? In my experience, here's the answer to both these questions: All. The. Time.

Am I right? Some days it feels like everyone who walks into my office has the same concern. So, why is everybody so damn tired all the time? Fatigue would seem to be the plague of our modern lives. If you find yourself in the chronically-tired camp, here are some common causes of fatigue:

1. Anemia

Iron deficiency is uber-common among young, otherwise healthy women. If you’re premenopausal (or even perimenopausal)[1] you’re losing blood monthly, which means a loss of iron. But replenishing that iron is difficult to do. Iron is a tricky mineral for our bodies to absorb. And this can be a particular problem if you’re vegetarian, or not a big fan of meat in general. Meat is our best source of iron, but you can definitely get it from other sources (see here[2]). Anemia is very easily diagnosed with a blood test.

2. Underactive Thyroid

Thyroid hormone is a key “metabolism hormone,” meaning: if you don’t have enough of it, you can feel sluggish, gain weight, feel cold, get constipated, and suffer hair loss. And here’s a little truth I’ve noticed in my years of practice: everybody secretly wants to be told they have hypothyroidism. Really. It’s like the holy grail of diagnoses: a tidy explanation for why you’re feeling tired and gaining weight? And it’s treatable? Sign me up, please.

As a result, people are always disappointed when I tell them their thyroid tests came back perfectly normal. That said, hypothyroidism is extremely common, so you should certainly get tested if you have some of the above symptoms or a family history.

3. Pregnancy

If you’re reading this blog, you’re probably familiar with this one. But it’s amazing how many women don’t think of pregnancy when they start feeling tired. Especially if more kids weren’t exactly part of the plan, at the moment. Again, easily tested. Don’t ignore this possibility.

4. Sleep Apnea

You might think you’re getting enough sleep. But what if your sleep is being repeatedly interrupted, and you’re not even aware of it? Sleep apnea is when you stop breathing, momentarily, which briefly wakes you up—although most people have no recollection of this happening. It can occur hundreds of times a night, which translates to a sleep that’s anything but restful. Sleep apnea can be sneaky, but here’s a clue: does your sleeping partner comment on your loud snoring? Smoking, and being overweight are other risk factors. If you’re wondering about this one, talk to your doctor—certain tests can confirm this diagnosis.

5. Depression

Depression comes in many flavours: major depression, postpartum depression[3], dysthymia...but they all have one symptom in common: fatigue. The signs and symptoms of depression can sneak up on you, and sometimes it’s difficult to have insight into what’s going on. It’s easy to think: there must be a physical reason for experiencing the physical symptom of fatigue. But that’s a mistake. Especially if it stops you from getting the help you need.

Now, the above five illnesses are very specific entities that cause tiredness. And they are important things that need to be ruled out. But...truth be told, the vast majority of fatigue is due to lifestyle factors.

Of course “lifestyle” is a nebulous category, to be sure. It comprises a whole bunch of things that are much trickier to tackle than, say, popping a thyroid pill. But there’s a good chance one of these issues (or, more likely—all of them, to varying degrees) are at the root of your fatigue. The next five items on the list are common lifestyle culprits that zap your energy:

6. Not sleeping enough

Yes, we’ve all got lots to do, and staying up just a little later to knock off a few more things from your list is tempting. But resist the temptation. Put yourself to bed, instead. (Sleep not coming easily? Read this[4].)

7. Not eating enough

I know, you’re trying to trim your midsection (as we all are[5])...but if you’re not eating enough to meet your energy needs through the day, guess what’s going to suffer? Here’s a key strategy: have protein-rich snacks [6]during the day: they’re great for metabolism, great for energy, and much less likely to contribute to your muffin top.

8. Not exercising enough

I know, when you’re exhausted, the last thing you want to do is exercise. Surely that’ll only make you more tired, right? Trust me, the opposite is true. Exercise breeds energy. A brisk walk, a yoga class (or even just some stretches in your living room), or a nice bike ride will have amazing rejuvenating effects—both short-term and long.

9. Not drinking enough

And I don’t mean lattes. Or mojitos. I’m just talking plain old water, here. A lot of us walk around with a mild degree of dehydration. Not enough to threaten your health, exactly, but enough to make you feel awfully sluggish. How much water should you drink? Read this[7].

10. Too stressed

Stress is a tough one. It’s ubiquitous. And certain seasons of life are more stress-inducing than others, that’s for sure. (Life with a newborn, anyone? Divorce? Death of a family member? Re-entering the workplace?) Stress is a HUGE cause of fatigue. Dealing with said stress is a whole other can of worms, though. Good news: there’s a lot you can do. Here’s a starting point[8].

Now, this is not a complete list. Fatigue is an extremely nonspecific symptom that rears its head due to a whole lot of things; I’ve just listed some of the top causes here. Essentially, if you’ve been battling fatigue for a while, do what you can to optimize your lifestyle, and pay a visit to your doctor.

As a footnote, when I was writing this post, I felt tempted to list “motherhood” as a cause for fatigue. Because I have yet to meet a mother—especially one who has really little kids—who doesn’t feel tired most of the time. But I don’t think it has to be that way. Meaning: don’t give up! A certain degree of acceptance is helpful when it comes to motherhood (leaning into it[9], I like to say)...but on the other hand, I encourage you to keep working at a healthy lifestyle. It takes creativity and a certain tenaciousness to carve out time for exercise, for example, and to eat well (when everyone else in your household would be happy to survive on mac & cheese every day. Ahem.) But don’t succumb. Don’t be that girl. If for no other reason than: you deserve better.